On the multiplicity function of ergodic group extensions of rotations
Volume 102 / 1992
Studia Mathematica 102 (1992), 157-174
DOI: 10.4064/sm-102-2-157-174
Abstract
For an arbitrary set A ⊆ ℕ satisfying 1 ∈ A and lcm(m₁,m₂) ∈ A whenever m₁,m₂ ∈ A, an ergodic abelian group extension of a rotation for which the range of the multiplicity function equals A is constructed.
